Abstract
Brownian colloidal particles dispersed in a fluid with a temperature gradient experience a driving force which produces a large biased steady density profile. This phenomenon, named thermophoresis, is quantified by the Soret coefficient \(S_T\). This problem is studied here within the Fokker–Planck formalism. Using the experimental observation of \(S_T\) it is possible to extract relevant analytical information about a temperature dependent nonequilibrium effective potential which can produce the thermophoresis force. It will be presented here a statistical physics derivation of this effective potential in terms of some physical parameters. Experimental data are analyzed within this theoretical scenario.
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Acknowledgements
We acknowledge financial support by the Ministerio de Economía y Competitividad (Spain) and FEDER (EU), under project FIS2015-66503-C3-P3, and fruitful discussions with Profs. R. Toral, Pietro Tierno, L. Ramírez–Piscina and M. Ibañes .
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Sancho, J.M. Statistical Physics Approach to Thermophoresis of Colloids. J Stat Phys 172, 1609–1616 (2018). https://doi.org/10.1007/s10955-018-2110-1
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DOI: https://doi.org/10.1007/s10955-018-2110-1